Re: tipc_init(), WARNING: at arch/x86/mm/highmem_32.c:52, [2.6.24-rc4-git5: Reported regressions from 2.6.23]

Linus Torvalds
2007-12-08T17:55:26Z

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On Sat, 8 Dec 2007, Linus Torvalds wrote:
>
> But I'll apply it anyway, because it looks "obviously correct" from the
> standpoint that the _other_ slob user already clears the end result
> explicitly later on, and we simply should never pass down __GFP_ZERO to
> the actual page allocator.

Actually, I take that back. The other slob users are different. They share
pages, this codepath does not.

So I think a more proper solution would be:
(a) Something like this patch (which includes my previous mm/slub.c
change)
(b) don't warn about atomic GFP_ZERO's - unless they have GFP_HIGHMEM set
*too*.

So which warning is it that triggers the bogus error?

Linus
---
mm/slob.c | 2 +-
mm/slub.c | 3 +++
2 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/mm/slob.c b/mm/slob.c
index ee2ef8a..773a7aa 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -330,7 +330,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)

/* Not enough space: must allocate a new page */
if (!b) {
- b = slob_new_page(gfp, 0, node);
+ b = slob_new_page(gfp & ~__GFP_ZERO, 0, node);
if (!b)
return 0;
sp = (struct slob_page *)virt_to_page(b);
diff --git a/mm/slub.c b/mm/slub.c
index b9f37cb..9c1d9f3 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1468,6 +1468,9 @@ static void *__slab_alloc(struct kmem_cache *s,
void **object;
struct page *new;

+ /* We handle __GFP_ZERO in the caller */
+ gfpflags &= ~__GFP_ZERO;
+
if (!c->page)
goto new_slab;